When hydrogen is replaced by another element in a hydrocarbon, the reaction is called hydrogenation addition substitution redox

substitution

Explanation:

Hydrogenation is defined as a chemical reaction in which hydrogens are added to hydrocarbons using reducing agents.

Addition reaction is defined as the reaction in which two reactants get added to give single product.

Substitution reaction is defined as the reaction in which one atom replaces the other atom from the compound.

Redox reaction is defined as the reaction in which oxidation and reduction reactions occur simultaneously. Oxidation reaction is defined as the reaction in which a substance looses its electrons.Reduction reaction is defined as the reaction in which a substance gains electrons.

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explanation:

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